Food processors are available which generally include a working bowl with a motor driven shaft projecting into the bowl on which various selected rotary tools can be engaged to be driven by the shaft for performing various food processing operations, such as cutting, slicing, grating, etc. A detachable cover which is secured over the top of the bowl during use includes a hopper or feed tube which has a mouth opening downwardly through the cover into the top of the bowl. The food items to be prepared are placed in the feed tube and pushed down through the feed tube into the bowl by means of a removable, manually operable pusher member which is adapted to slide down in a manner of a plunger into the feed tube, thereby bringing the food items into contact with the rotary tool being employed. Additional information with respect to this type of automatic food processing apparatus may be obtained from U.S. Pat. Nos. 3,892,365 to Pierre Verdon; 3,985,304 to the present inventor; and 4,127,342 to Marcel Coggiola.
Of particular interest to the present invention is the rotary cutting tool which is used for slicing food items such as cucumbers, onions, potatoes, carrots, celery, cabbage, squash, beets, avacado, etc. Such a rotary slicing tool has a horizontal disc-like member formed of sheet metal, preferably stainless steel, which is mounted on an elongated hub extending down in the bowl of the food processor and engaged onto the motor-driven shaft. The disc-like member has a horizontal area which may include a down-turned flange around its perimeter and has an arcuate slot extending from the hub out to the periphery of the disc-like member. An arcuate slicing blade is mounted on the disc-like member behind the slot with its cutting edge projecting forward and elevated above the level of the horizontal area and facing forward above the slot for slicing of food items, with the delicate slices of food passing down through the slot.
In the prior art such rotary slicing tools are characterized by having a sharply sloping shoulder on which an arcuate rim is formed overlying the arcuate slot with the slicing blade being mounted on this rim. As seen in plan view the sharply sloping shoulder intersects with the cutting edge near the periphery of the disc-like member and converges with the cutting edge near the hub. Thus, this sharply sloping shoulder interferes with the uniform slicing of food items near both extremities of the slicing blade, and particularly so in the region near the periphery of the disc-like member, where the relative velocity of this sharply sloping shoulder near the periphery of the fast-turning tool is high with respect to the stationary food item being sliced.
Interference by the shoulder in this peripheral region with the slices being formed causes smashing, shreading or stripping of the slices, thereby rendering them unattractive in appearance and often partially destroying the slices and severing narrow strips of food material from the side edges of an incompleted slice. A uniform and complete slicing operation is not performed by such prior art slicing tools. In effect, the fast-travelling sharply sloping shoulder on a prior art rotary slicing tool tends to clobber the delicate slices being formed. This impacting action of the sharply sloping portion of the disc along its entire length may waste a portion of the food item, may pulverize, smash, strip or shred a portion of the slice or may otherwise interfere with the desired neat slicing function.
Moreover, the impact with the slice being formed of this sharply sloping portion of the disc along its entire length (and particularly so near the periphery of the disc where relative velocities are greatest) often splatters fragments of the food and juices over substantially the entire inner surface of the wall of the working bowl. Such a splattering is unattractive and requires considerable clean up of the bowl.